netlabel: use domain based selectors when address based selectors are not available

NetLabel has the ability to selectively assign network security labels
to outbound traffic based on either the LSM's "domain" (different for
each LSM), the network destination, or a combination of both.  Depending
on the type of traffic, local or forwarded, and the type of traffic
selector, domain or address based, different hooks are used to label the
traffic; the goal being minimal overhead.

Unfortunately, there is a bug such that a system using NetLabel domain
based traffic selectors does not correctly label outbound local traffic
that is not assigned to a socket.  The issue is that in these cases
the associated NetLabel hook only looks at the address based selectors
and not the domain based selectors.  This patch corrects this by
checking both the domain and address based selectors so that the correct
labeling is applied, regardless of the configuration type.

In order to acomplish this fix, this patch also simplifies some of the
NetLabel domainhash structures to use a more common outbound traffic
mapping type: struct netlbl_dommap_def.  This simplifies some of the code
in this patch and paves the way for further simplifications in the
future.

Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 49 insertions, 55 deletions

diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
index 6bb1d42f0fac..85d842e6e431 100644
--- a/net/netlabel/netlabel_domainhash.c
+++ b/net/netlabel/netlabel_domainhash.c
@@ -84,15 +84,15 @@ static void netlbl_domhsh_free_entry(struct rcu_head *entry)
 #endif /* IPv6 */
 
 	ptr = container_of(entry, struct netlbl_dom_map, rcu);
-	if (ptr->type == NETLBL_NLTYPE_ADDRSELECT) {
+	if (ptr->def.type == NETLBL_NLTYPE_ADDRSELECT) {
 		netlbl_af4list_foreach_safe(iter4, tmp4,
-					    &ptr->type_def.addrsel->list4) {
+					    &ptr->def.addrsel->list4) {
 			netlbl_af4list_remove_entry(iter4);
 			kfree(netlbl_domhsh_addr4_entry(iter4));
 		}
 #if IS_ENABLED(CONFIG_IPV6)
 		netlbl_af6list_foreach_safe(iter6, tmp6,
-					    &ptr->type_def.addrsel->list6) {
+					    &ptr->def.addrsel->list6) {
 			netlbl_af6list_remove_entry(iter6);
 			kfree(netlbl_domhsh_addr6_entry(iter6));
 		}
@@ -213,21 +213,21 @@ static void netlbl_domhsh_audit_add(struct netlbl_dom_map *entry,
 		if (addr4 != NULL) {
 			struct netlbl_domaddr4_map *map4;
 			map4 = netlbl_domhsh_addr4_entry(addr4);
-			type = map4->type;
-			cipsov4 = map4->type_def.cipsov4;
+			type = map4->def.type;
+			cipsov4 = map4->def.cipso;
 			netlbl_af4list_audit_addr(audit_buf, 0, NULL,
 						  addr4->addr, addr4->mask);
 #if IS_ENABLED(CONFIG_IPV6)
 		} else if (addr6 != NULL) {
 			struct netlbl_domaddr6_map *map6;
 			map6 = netlbl_domhsh_addr6_entry(addr6);
-			type = map6->type;
+			type = map6->def.type;
 			netlbl_af6list_audit_addr(audit_buf, 0, NULL,
 						  &addr6->addr, &addr6->mask);
 #endif /* IPv6 */
 		} else {
-			type = entry->type;
-			cipsov4 = entry->type_def.cipsov4;
+			type = entry->def.type;
+			cipsov4 = entry->def.cipso;
 		}
 		switch (type) {
 		case NETLBL_NLTYPE_UNLABELED:
@@ -265,26 +265,25 @@ static int netlbl_domhsh_validate(const struct netlbl_dom_map *entry)
 	if (entry == NULL)
 		return -EINVAL;
 
-	switch (entry->type) {
+	switch (entry->def.type) {
 	case NETLBL_NLTYPE_UNLABELED:
-		if (entry->type_def.cipsov4 != NULL ||
-		    entry->type_def.addrsel != NULL)
+		if (entry->def.cipso != NULL || entry->def.addrsel != NULL)
 			return -EINVAL;
 		break;
 	case NETLBL_NLTYPE_CIPSOV4:
-		if (entry->type_def.cipsov4 == NULL)
+		if (entry->def.cipso == NULL)
 			return -EINVAL;
 		break;
 	case NETLBL_NLTYPE_ADDRSELECT:
-		netlbl_af4list_foreach(iter4, &entry->type_def.addrsel->list4) {
+		netlbl_af4list_foreach(iter4, &entry->def.addrsel->list4) {
 			map4 = netlbl_domhsh_addr4_entry(iter4);
-			switch (map4->type) {
+			switch (map4->def.type) {
 			case NETLBL_NLTYPE_UNLABELED:
-				if (map4->type_def.cipsov4 != NULL)
+				if (map4->def.cipso != NULL)
 					return -EINVAL;
 				break;
 			case NETLBL_NLTYPE_CIPSOV4:
-				if (map4->type_def.cipsov4 == NULL)
+				if (map4->def.cipso == NULL)
 					return -EINVAL;
 				break;
 			default:
@@ -292,9 +291,9 @@ static int netlbl_domhsh_validate(const struct netlbl_dom_map *entry)
 			}
 		}
 #if IS_ENABLED(CONFIG_IPV6)
-		netlbl_af6list_foreach(iter6, &entry->type_def.addrsel->list6) {
+		netlbl_af6list_foreach(iter6, &entry->def.addrsel->list6) {
 			map6 = netlbl_domhsh_addr6_entry(iter6);
-			switch (map6->type) {
+			switch (map6->def.type) {
 			case NETLBL_NLTYPE_UNLABELED:
 				break;
 			default:
@@ -402,32 +401,31 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry,
 			rcu_assign_pointer(netlbl_domhsh_def, entry);
 		}
 
-		if (entry->type == NETLBL_NLTYPE_ADDRSELECT) {
+		if (entry->def.type == NETLBL_NLTYPE_ADDRSELECT) {
 			netlbl_af4list_foreach_rcu(iter4,
-					       &entry->type_def.addrsel->list4)
+						   &entry->def.addrsel->list4)
 				netlbl_domhsh_audit_add(entry, iter4, NULL,
 							ret_val, audit_info);
 #if IS_ENABLED(CONFIG_IPV6)
 			netlbl_af6list_foreach_rcu(iter6,
-					       &entry->type_def.addrsel->list6)
+						   &entry->def.addrsel->list6)
 				netlbl_domhsh_audit_add(entry, NULL, iter6,
 							ret_val, audit_info);
 #endif /* IPv6 */
 		} else
 			netlbl_domhsh_audit_add(entry, NULL, NULL,
 						ret_val, audit_info);
-	} else if (entry_old->type == NETLBL_NLTYPE_ADDRSELECT &&
-		   entry->type == NETLBL_NLTYPE_ADDRSELECT) {
+	} else if (entry_old->def.type == NETLBL_NLTYPE_ADDRSELECT &&
+		   entry->def.type == NETLBL_NLTYPE_ADDRSELECT) {
 		struct list_head *old_list4;
 		struct list_head *old_list6;
 
-		old_list4 = &entry_old->type_def.addrsel->list4;
-		old_list6 = &entry_old->type_def.addrsel->list6;
+		old_list4 = &entry_old->def.addrsel->list4;
+		old_list6 = &entry_old->def.addrsel->list6;
 
 		/* we only allow the addition of address selectors if all of
 		 * the selectors do not exist in the existing domain map */
-		netlbl_af4list_foreach_rcu(iter4,
-					   &entry->type_def.addrsel->list4)
+		netlbl_af4list_foreach_rcu(iter4, &entry->def.addrsel->list4)
 			if (netlbl_af4list_search_exact(iter4->addr,
 							iter4->mask,
 							old_list4)) {
@@ -435,8 +433,7 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry,
 				goto add_return;
 			}
 #if IS_ENABLED(CONFIG_IPV6)
-		netlbl_af6list_foreach_rcu(iter6,
-					   &entry->type_def.addrsel->list6)
+		netlbl_af6list_foreach_rcu(iter6, &entry->def.addrsel->list6)
 			if (netlbl_af6list_search_exact(&iter6->addr,
 							&iter6->mask,
 							old_list6)) {
@@ -446,7 +443,7 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry,
 #endif /* IPv6 */
 
 		netlbl_af4list_foreach_safe(iter4, tmp4,
-					    &entry->type_def.addrsel->list4) {
+					    &entry->def.addrsel->list4) {
 			netlbl_af4list_remove_entry(iter4);
 			iter4->valid = 1;
 			ret_val = netlbl_af4list_add(iter4, old_list4);
@@ -457,7 +454,7 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry,
 		}
 #if IS_ENABLED(CONFIG_IPV6)
 		netlbl_af6list_foreach_safe(iter6, tmp6,
-					    &entry->type_def.addrsel->list6) {
+					    &entry->def.addrsel->list6) {
 			netlbl_af6list_remove_entry(iter6);
 			iter6->valid = 1;
 			ret_val = netlbl_af6list_add(iter6, old_list6);
@@ -538,18 +535,18 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry,
 		struct netlbl_af4list *iter4;
 		struct netlbl_domaddr4_map *map4;
 
-		switch (entry->type) {
+		switch (entry->def.type) {
 		case NETLBL_NLTYPE_ADDRSELECT:
 			netlbl_af4list_foreach_rcu(iter4,
-					     &entry->type_def.addrsel->list4) {
+					     &entry->def.addrsel->list4) {
 				map4 = netlbl_domhsh_addr4_entry(iter4);
-				cipso_v4_doi_putdef(map4->type_def.cipsov4);
+				cipso_v4_doi_putdef(map4->def.cipso);
 			}
 			/* no need to check the IPv6 list since we currently
 			 * support only unlabeled protocols for IPv6 */
 			break;
 		case NETLBL_NLTYPE_CIPSOV4:
-			cipso_v4_doi_putdef(entry->type_def.cipsov4);
+			cipso_v4_doi_putdef(entry->def.cipso);
 			break;
 		}
 		call_rcu(&entry->rcu, netlbl_domhsh_free_entry);
@@ -590,20 +587,21 @@ int netlbl_domhsh_remove_af4(const char *domain,
 		entry_map = netlbl_domhsh_search(domain);
 	else
 		entry_map = netlbl_domhsh_search_def(domain);
-	if (entry_map == NULL || entry_map->type != NETLBL_NLTYPE_ADDRSELECT)
+	if (entry_map == NULL ||
+	    entry_map->def.type != NETLBL_NLTYPE_ADDRSELECT)
 		goto remove_af4_failure;
 
 	spin_lock(&netlbl_domhsh_lock);
 	entry_addr = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
-					   &entry_map->type_def.addrsel->list4);
+					   &entry_map->def.addrsel->list4);
 	spin_unlock(&netlbl_domhsh_lock);
 
 	if (entry_addr == NULL)
 		goto remove_af4_failure;
-	netlbl_af4list_foreach_rcu(iter4, &entry_map->type_def.addrsel->list4)
+	netlbl_af4list_foreach_rcu(iter4, &entry_map->def.addrsel->list4)
 		goto remove_af4_single_addr;
 #if IS_ENABLED(CONFIG_IPV6)
-	netlbl_af6list_foreach_rcu(iter6, &entry_map->type_def.addrsel->list6)
+	netlbl_af6list_foreach_rcu(iter6, &entry_map->def.addrsel->list6)
 		goto remove_af4_single_addr;
 #endif /* IPv6 */
 	/* the domain mapping is empty so remove it from the mapping table */
@@ -616,7 +614,7 @@ remove_af4_single_addr:
 	 * shouldn't be a problem */
 	synchronize_rcu();
 	entry = netlbl_domhsh_addr4_entry(entry_addr);
-	cipso_v4_doi_putdef(entry->type_def.cipsov4);
+	cipso_v4_doi_putdef(entry->def.cipso);
 	kfree(entry);
 	return 0;
 
@@ -693,8 +691,8 @@ struct netlbl_dom_map *netlbl_domhsh_getentry(const char *domain)
  * responsible for ensuring that rcu_read_[un]lock() is called.
  *
  */
-struct netlbl_domaddr4_map *netlbl_domhsh_getentry_af4(const char *domain,
-						       __be32 addr)
+struct netlbl_dommap_def *netlbl_domhsh_getentry_af4(const char *domain,
+						     __be32 addr)
 {
 	struct netlbl_dom_map *dom_iter;
 	struct netlbl_af4list *addr_iter;
@@ -702,15 +700,13 @@ struct netlbl_domaddr4_map *netlbl_domhsh_getentry_af4(const char *domain,
 	dom_iter = netlbl_domhsh_search_def(domain);
 	if (dom_iter == NULL)
 		return NULL;
-	if (dom_iter->type != NETLBL_NLTYPE_ADDRSELECT)
-		return NULL;
 
-	addr_iter = netlbl_af4list_search(addr,
-					  &dom_iter->type_def.addrsel->list4);
+	if (dom_iter->def.type != NETLBL_NLTYPE_ADDRSELECT)
+		return &dom_iter->def;
+	addr_iter = netlbl_af4list_search(addr, &dom_iter->def.addrsel->list4);
 	if (addr_iter == NULL)
 		return NULL;
-
-	return netlbl_domhsh_addr4_entry(addr_iter);
+	return &(netlbl_domhsh_addr4_entry(addr_iter)->def);
 }
 
 #if IS_ENABLED(CONFIG_IPV6)
@@ -725,7 +721,7 @@ struct netlbl_domaddr4_map *netlbl_domhsh_getentry_af4(const char *domain,
  * responsible for ensuring that rcu_read_[un]lock() is called.
  *
  */
-struct netlbl_domaddr6_map *netlbl_domhsh_getentry_af6(const char *domain,
+struct netlbl_dommap_def *netlbl_domhsh_getentry_af6(const char *domain,
 						   const struct in6_addr *addr)
 {
 	struct netlbl_dom_map *dom_iter;
@@ -734,15 +730,13 @@ struct netlbl_domaddr6_map *netlbl_domhsh_getentry_af6(const char *domain,
 	dom_iter = netlbl_domhsh_search_def(domain);
 	if (dom_iter == NULL)
 		return NULL;
-	if (dom_iter->type != NETLBL_NLTYPE_ADDRSELECT)
-		return NULL;
 
-	addr_iter = netlbl_af6list_search(addr,
-					  &dom_iter->type_def.addrsel->list6);
+	if (dom_iter->def.type != NETLBL_NLTYPE_ADDRSELECT)
+		return &dom_iter->def;
+	addr_iter = netlbl_af6list_search(addr, &dom_iter->def.addrsel->list6);
 	if (addr_iter == NULL)
 		return NULL;
-
-	return netlbl_domhsh_addr6_entry(addr_iter);
+	return &(netlbl_domhsh_addr6_entry(addr_iter)->def);
 }
 #endif /* IPv6 */